Many processes can be found in the technical and patent literature describing procedures to reduce the carry over of fines in vapor streams produced during drying of a solid particles mass following treatment of the particles with a liquid. Most of such literature deals with means to prevent the production of fines and/or wash fines away for further treatment to recover them in a secondary fines recovery from a liquid. Other processes utilize cyclones, bag houses, electrostatic precipitation, as well as liquid quench of a gas stream carrying the fines.
Each of these techniques has some disadvantages besides requiring special and often high initial capital and/or operating expense, e.g. bag houses are labor and utilities intensive, cyclones are subject to mechanical erosion and are limited in particle size efficiency, as are electrostatic precipitators, while quench techniques usually require a high purity quench liquid and a solids from liquid separation step.
It would therefore be advantageous to have a technique whereby the fines associated with a mass of solid particles which have been treated with a liquid organic solvent, which solids may be attritable during or prior to a liquid removal step, can be maintained with the mass while subjecting the mass to a liquid removal operation.